I don't think its tacky, but I so love getting cards in the mail and I even like the newsletters that make everyone's lives seem better than they are. I have an area of my wall dedicated to taping up the cards (which, I admit, may be tacky).
since my dh is x-mil and I'm halfway across the country from my family of origin, our family & friends are scattered far & wide, so I can feel your pain about the cost involved. I also take the time to sign each of my cards personally, and add a little personal note to 99% of them....it is a big investment of time and money, but I look at as a small price to pay to keep in touch with people who are or at one time were important to us.